[SOLVED] CPU water cooler - Burnt smells

azurin

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Apr 2, 2011
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Hello there!

I'm getting burnt smells coming from my PC whenever I do moderately intense gaming. (Rather old games, but just enough to make the PC work harder than, say, video streaming) I thought for a while it might be the PSU, but the smell was rather strong this afternoon. I put my nose behind the PC, and to my surprise it seemed to be coming from the water cooler fan rather than the PSU. I tried getting answers on the internet, but everybody says it's the PSU, or the topic ends up dead. Here's some details

-The rig is old - 9 years, and never ran too hot.
-I cleaned the PC last week.
-The PSU is a (one year old) Seasonic M12II 620w. (It's an old design, I know. This has already been discussed)

Running on...
CPU - FX-8320
Motherboard - M5A97 R2.0
GPU - Radeon R7 250
RAM - Kingston 8gb ddr3 1600

Temps from parts in general running between 30 - 60c (Idle - Under pressure)


I'd like to have your advice in this matter. Logic and known facts point out the PSU, but current facts here point the water cooler...which is rather undocumented.
Thank you very for your help, it is much appreciated!
 
Solution
Lifespans of modern fans are usually from 40,000 hrs to @ 100,000hrs. So figure @ 5-10 years. So figure bearings are worn, lubricant is running dry, there's however many years worth of dust packed into the tiny gap between fan hub and motor housing. It happens. Best way to know for sure is just pull the fan off the rad and stick your nose upto the back of the motor. It shouldn't be all that warm to touch. If it is, and has that definite acrid burnt smell, replace the fan with a new one, it's done, toast.

Karadjgne

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Lifespans of modern fans are usually from 40,000 hrs to @ 100,000hrs. So figure @ 5-10 years. So figure bearings are worn, lubricant is running dry, there's however many years worth of dust packed into the tiny gap between fan hub and motor housing. It happens. Best way to know for sure is just pull the fan off the rad and stick your nose upto the back of the motor. It shouldn't be all that warm to touch. If it is, and has that definite acrid burnt smell, replace the fan with a new one, it's done, toast.
 
Solution

azurin

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Apr 2, 2011
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Hello,

Sorry for the late reply, I just came back home since yesterday.

The PC wasn't on, so as soon as I get it on, and it gets a bit hotter from activity, I'll do just as you suggested. I'll give you news whether the back of the motor is hot or not, and has a specific smell. I understand about the fan, but I do not understand the link between a fan that made its time and the dusty back of a motor...it looks like two separate cases to me. (Like a dusty PSU and a faulty one)

Thank you very much for your help!
 

Karadjgne

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Dust from blowback and/or turbulence can enter the tiny gap between the solid motor mount and the fan blades hub. It'll get trapped in there like corn in an old fashioned stone grinder mill, building up over time, mixing with lubricants, creating mud or eventually packing in so tight it becomes like a brake, forcing the motor to work harder just to spin the fan. The harder a motor works (not necessarily faster) , the more amps it pulls, jacking up the heat. Friction with the dust also creates heat. End result is usually a dead fan, either the pcb burns up, the motor burns out or the bearings get so hot they melt the plastic retainer.
 

azurin

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Apr 2, 2011
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Oh, I see. Thank you for the explanation.

After two days, strangely enough, the smell did not come back. It can be worth noting that the PC runs nearly 24h/7 days, and that 24 hour break is something quite rare for the engine. In a way, the problem no longer seems to be there, but what I've learnt about the motor, and the fan that will have done its time sooner or later, is something I intend to remember and a new step in my rig maintenance. I'll see whenever the problem presents itself again.

Thank you very much for enlightening me on the matter, much appreciated.